A navigation system performs travel guidance for enabling a user to easily and quickly reach the selected destination. A typical example is a vehicle navigation system where a user's vehicle is equipped with a navigation function. Such a navigation system detects the position of the user or user's vehicle, and reads out map data pertaining to an area at the current vehicle position from a data storage medium, for example, a DVD (digital versatile disc), or a hard disc. Alternatively, such map data can be provided to the user from a remote server through a communication network such as Internet.
When a destination is set, the navigation system starts a route guidance function for setting a guided route from the start point to the destination. During the route guidance, the navigation system reads the nodes data from the data storage medium and successively stores the nodes data of road segments constituting the guided route in a map memory. In the actual traveling, the node series stored in the map memory is searched for a portion of the guided route to be displayed in a map display area of the monitor screen, and the portion of the guided route is highlighted to be clearly distinguished from other routes.
FIGS. 1A–1F show an example of procedure and screen display involved in the navigation system for specifying a destination and guiding the user to the destination. A main menu screen such as shown in FIG. 1A displays menu items including a “Destination” menu for entering the destination. When selecting “Destination”, the navigation system displays a “Find Destination by” screen as shown in FIG. 1B for selecting an input method for specifying the destination. The “Find Destination By” screen lists various methods for selecting the destination including “Address” for specifying the city and address of the destination, “Intersection” for specifying the names of two streets which intersect with one another, and “Point of Interest” (POI) for selecting the programmed destination based on the name, category or telephone number. Other methods in the “Find Destination by” screen include “Recent Route” for specifying the destination based on the recent history of destinations saved in the navigation system, and “Address Book” for selecting the address of the destination from a prescribed address list stored in the system.
When selecting, for example, the “Point of Interest” method in FIG. 1B, the navigation system displays selection methods of point of interest (POI) either by “Place Name” or “Place Type” in FIG. 1C. The “Place Name” is to specify a name of POI, and the “Place Type” is to specify a category of POI. If the “Place Name” is selected in FIG. 1C, the navigation system shows an “Enter Place Name” screen such as shown in FIG. 1D. The screen of FIG. 1D is basically a keyboard for inputting the name in an input box on the monitor screen. The user inputs the name of the desired POI in the input box through the keyboard.
FIG. 1E shows a “Confirm Route” screen of the navigation system for confirming the destination. If the place name displayed is the correct destination, the user enters an “OK to Proceed” key to proceed to the next procedure. Then, the navigation system calculates and determines a guided route to the destination, i.e., the selected POI. After determining the guided route, the navigation system starts the route guidance as shown in FIG. 1F. Typically, the navigation system shows the intersection which is highlighted to show the next turn and a direction of the turn. Such route guidance by the navigation system is also given by voice instructions.
As noted above, typically, a user inputs an address or a name of a particular point of interest by using a keyboard as shown in FIG. 1D for setting a destination. In the case where the user has made a mistake in inputting the address or name of the destination, the user had to return to the point where the mistake is made in order to correct the mistake.
FIGS. 2A–2C show the process for correcting a wrong entry in such a situation. FIGS. 2A and 2B show an example of display where a user has inputted a place name “Joey Mobil” in a text window 27 through a keyboard 28. Suppose the correct place name is “Jody Mobil” and the user wants to correct the error. Thus, in this case, the user wants to change the letter “e” to “d”.
In the conventional navigation system, the user has to delete the letters in the text window with use of a “delete” key to move the cursor backward to arrive at the letter “e” as shown in FIG. 2C. In other words, the letters that have been already inputted have to be deleted by this process even though most of them are correct. In this example, the letters “y Mobil” are erased even though all of them are correct. Namely, when the user has to correct the single letter, she has to re-type the rest of the letters.
There is also a situation where the user does not know the exact name of the destination. For example, the user wants to visit a particular gas station whose name is “Jody Mobil” in the above example, however, she knows only that the name ends with “Mobil”. The user may know that the first word of the place name to visit starts with “Jo” and ends with the letter “y”, but she is not certain whether it is “Joey”, “Joay” or “Jody”, etc. Thus, it is desirable for the user to know what a letter comes between them to specify the location to visit without repeatedly typing the correct letters.
Thus, what is needed is a navigation system having an improved key correction function for inputting text data which allows the user to move a cursor to a particular location where a mistake is made or correctness is not certain, and provides a feedback to the user by searching the possible letter from the database.